miercuri, 24 februarie 2010

Quiz: Join Clauses

Test: Quiz: Join Clauses
Review your answers, feedback, and question scores below. An asterisk (*) indicates a correct answer.
Section 1

1. The primary advantage of using JOIN ON is: Mark for Review
(1) Points


The join happens automatically based on matching column names and data types


It will display rows that do not meet the join condition


It easily produces a Cartesian product between the tables in the statement


It permits columns that don?t have matching data types to be joined


It permits columns with different names to be joined (*)



Correct Correct


2. The keywords JOIN _____________ should be used to join tables with the same column names but different datatypes. Mark for Review
(1) Points


NATURAL ON


ON


WHEN


USING (*)



Correct Correct


3. The following is a valid SQL statement.

SELECT e.employee_id, e.last_name, d.location_id, department_id
FROM employees e JOIN departments d
USING (department_id) ;

True or False?
Mark for Review
(1) Points


True (*)


False



Correct Correct


4. Table aliases MUST be used with columns referenced in the JOIN USING clause. True or False? Mark for Review
(1) Points


True


False (*)



Correct Correct


5. You can do nonequi-joins with ANSI-Syntax. True or False? Mark for Review
(1) Points


True (*)


False



Correct Correct



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